Performed by: Measures can be performed by the person affected (oral self-care) or by other persons, mainly medical specialists (professional oral-care).ĭisease pattern: Prophylaxis, which is completed on healthy patients ( primary prophylaxis), should be differentiated from early detection of incipient disease processes (screening, secondary prophylaxis) and the prevention of relapses after completed treatment (tertiary prophylaxis). clarification about and application of behaviour patterns, mechanical and technical aids, preventive use of pharmacological and chemical active agents or vaccines. Methods: Different types of methods can be used for prophylaxis, e.g. They are differentiated according to age group as infant-, child-, adolescent-, adult- and geno-prophylaxis and also according to the current physical status as pregnancy prophylaxis or handicapped prophylaxis. Target group: They can be targeted at individual persons ( individual prophylaxis), a specific population ( group prophylaxis) or the entire population (collective prophylaxis). Prophylactic measures are classified according to various criteria: Nowadays the modern terms prophylaxis and prevention are often used synonymously. Chronologically, therefore, it mainly occurs prior to examinations for screening or early detection and minimally invasive treatment. The disadvantages of the material are that it absorbs water, so that it must be washed and dried as soon as it is removed from the mouth.Prophylaxis (from the Greek phylassein, "be vigilant") is a collective term for all measures taken to prevent from the outset any impairments to health, their persistence, increase or reoccurrence. What are the advantages and disadvantages of polysulfide and polyether impression material?Ī further advantage of polyether is its short setting time in the mouth (less than half the time required for polysulfide). Loss of water from the set material has a significant effect on the dimensional stability of the impression. The reaction yields water as a by-product. Which of the following controls the setting reaction of polysulfide?Įlevated temperature and humid conditions will accelerate the setting of polysulfide impression material. Recently, new elastomeric impression materials with very high elastic recovery and high tear strength have been introduced. For what are elastomeric impressions?Įlastomeric impression materials (addition silicones and polyethers) offer high elastic recovery and acceptable flexibility on removal of the impression from the mouth. In the hardened state, they are flexible and elastic.Įxamples of elastomers include natural rubbers, styrene-butadiene block copolymers, polyisoprene, polybutadiene, ethylene propylene rubber, ethylene propylene diene rubber, silicone elastomers, fluoroelastomers, polyurethane elastomers, and nitrile rubbers. The agar-type hydrocolloids are thermoplastic, elastic materials which are softened by heating, hardened by cooling, and used repeatedly. However in the dental industry, agar is used to make dental impressions. They can be used in a wide range of applications, such as: Aircraft fuel tank sealants. Master Bond polysulfides are versatile synthetic elastomers that are used in the electronic, electrical, computer, metalworking, appliance, automotive and chemical industries. Polyether, any of a class of organic substances prepared by joining together or polymerizing many molecules of simpler compounds (monomers) by establishing ether links between them polyethers, which may be either chainlike or networklike in molecular structure, comprise an unusually diverse group of polymers. They can be further categorized according to their end use. Polyester polyols are made by the polycondensation reaction of multifunctional carboxylic acids and polyhydroxyl compounds. Polyether polyols are made by the reaction of epoxides with compounds having active hydrogen atom.
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